Supply and demand are fundamental concepts in economics that describe the relationship between the availability of a product (supply) and the desire for that product (demand).
The law of demand states that, all else being equal, as the price of a good falls, the quantity demanded rises, and vice versa.
The law of supply states that as the price of a good rises, the quantity supplied rises, and vice versa.
The interaction between supply and demand determines the market price and quantity of goods and services that are bought and sold.
When supply matches demand, the market is in equilibrium.